Leif Garrett in 2005. / Kevin Winter, Getty Images

by Olivia Barker, USA TODAY

by Olivia Barker, USA TODAY

And though Justin Bieber certainly hasn't descended to the drug-addicted depths that Leif Garrett did, the '70s superboy has some sobering words for his '10s counterpart.

"Do not believe your own publicity," Garrett, 51, told Fox News. "Sussing out who your real friends are is full-time work. Every scum bag, every drug dealer, every chicken hawk wants a piece of you."

The I Was Made for Dancin' singer offered insight into the mind of a teen idol: "When you've got that sort of power at that young age and everything at your doorstep, you put out that bad boy image. At that age, testosterone, hormones, all of the money - you see what else you can get away with."

Garrett also drew a parallel between his on-and-off girlfriend of the era, Nicolette Sheridan, and Bieber's, Selena Gomez. "(Bieber) rented out the (L.A.) Staples Center for (Selena). Fame, money is what tore us apart. Nicolette just started modeling. My career was pretty much there. We would get along great or clear rooms. That's the whole thing with Justin and me: There was no in between â?¦ really good or really naughty."